Tube reviews for C/J Premier 17?

Anyone done any experimenting with which 6922's-Ec88's have the cleanest sonics in a C/J premier17. Any reviews would be greatly appreciated.
This isn,t an answer to your question but it brings to mind a question I have had for a while. There seems to be new and great versions of the 12ax7 from both Sovtek and Electro Harmonix(with is a division of Sovtek). Why no new 6922's? I would love to see an Electro Harmonx 6922/6Dj8 that had superior performance to the standard Sovtek. Seems like they would sell the hell out of them judging from the number of 6Dj8 based maps and pre amps out there and people like you and I out there.
I suggest you to get four Siemens CCa 6922s(no need for a matched quad)NOS tubes to replace stock tubes. They sound dynamic, more detail, transparent and luscious than telefunken CCa 6922s. Give a try and you will hear a big change.